Note: Descriptions are shown in the official language in which they were submitted.
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TAILGATE FOR MULTIPLE COMPARTMENT MATERIAL CONTAINER
BACKGROUND OF THE INVENTION
I. Field of the Invention
The present invention relates generally to vehicles
for collecting, transporting and unloading several sorted
classes of materials, that may include recyclable
materials, in which the truck body is in the form of a
generally hollow container mounted on a truck chassis and
having an internal volume split or compartmentalized into
two or more compartments, each equipped to receive, store
and discharge or eject materials separately. More
particularly, the present invention relates to a split
tailgate system that enables the separate operation of a
tailgate door for each compartment, but which maintains a
reduced center of gravity with reference to the vehicle
regardless of the position of the doors.
II. Related Art
The art of refuse collection is becoming
increasingly complex, particularly in view of the rising
interest in requirements with respect to recyclable
goods. Rules and requirements of recycling restrict co-
mingling of unlike materials such as paper with glass,
metal and plastic goods. These separately loaded and
stored materials must also be kept apart during the
discharge operation so that each associated compartment
must be capable of being unloaded to the exclusion of
others.
Vehicles of the class have been specifically
designed with refuse bodies arranged in several
compartments for the separate processing of segregated
materials. This includes the use of a split compartment
charging hopper for separately charging upper and lower
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storage compartments. The refuse body may employ a
single set of packing cylinders in conjunction with
connecting arms between upper and lower packers to
operate both packers or use individual dedicated
compacting mechanisms. Provision is made for separate
discharge from the upper and lower compartments.
Examples of these are shown and described in U.S. Patent
5,868,543 which illustrates a packing apparatus with a
multi-compartment storage body which includes a charging
hopper divided into upper and lower portions, each having
its own packing system. Front loading systems of the
class are shown in U.S. Patents 5,681,140 and 5,797,715,
all of which are assigned to the same assignee as the
present application.
A further tailgate design for a multiple compartment
rear discharge collection vehicle is shown in U.S. Patent
5,527,098 which allows access to each of two (upper and
lower) compartments in a rear discharging refuse body
using a plurality of doors which allows separate
operation. However, both doors are hinged at the top of
the refuse body. The opening of the doors at once owing
to the top hinging of both doors may, in certain
instances, raise the center of gravity of the system
sufficiently to adversely affect the. stability of the
vehicle. This is particularly true in the case of a dump
body unloading system in which the front of the container
is raised during the discharge operation and/or wherever
heavy material is loaded into the upper compartment.
It will readily be seen that a definite need remains
for a rear discharging, multiple compartment refuse
vehicle of the class that enables clear separate
discharge of stacked compartments with a minimal effect
on the center of gravity of a discharging vehicle.
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SUMMARY OF THE INVENTION
The present invention provides a tailgate system for
a split body collection vehicle which allows the separate
discharge of upper and lower longitudinally oriented
compartments in the storage container by the provision of
upper and lower discharge doors featuring a vertically
pivoting lower door which operates using a mid-body
hinging system and is shorter than the height of the
lower compartment and thereby introduces a vertical
unsealed gap between the doors. An auxiliary closure
device is provided to normally close the upper portion of
the lower compartment maintained by the upper portion of
the lower door. This unique construction provides
adequate clearance that enables the lower door to open
fully while the upper discharge door remains closed.
Conversely, the system also enables the upper door to
open alone fully or both to open at once, if desired,
each mutually clearing the other without sacrificing the
ability to fully expose the related compartment to allow
full ejection or requiring top hinging of the lower door.
In the detailed embodiment, each of the doors is
operated by a pair of oppositely disposed fluid cylinders
with associated rods which, upon extension, lift and
pivot the doors in a manner that accomplishes both
unlatching and opening using vertically adjustable hinge
pins that are designed to travel as followers along slots
provided. The auxiliary closure device is an
intermediate vertically pivoting plate member suspended
at the top of the lower compartment and, as stated, the
lower portion of the plate is normally held closed by the
upper portion of the lower door when the door is in the
closed position, but is allowed to freely pivot with the
lower door to expose the full discharge opening of the
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lower compartment when the lower door is open and thereby
to enable sufficient separation such that full open/close
independence is achieved by the stacked doors of the
tailgate system.
While the detailed description pertains to a
particular embodiment of the invention, it will be
appreciated that that embodiment is offered by way of
example rather than limitation with respect to the
underlying invention and those skilled in the art will
appreciate that other embodiments could be used as well.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings, wherein like numerals are utilized
to designate like parts throughout the same:
Figure 1 illustrates a prior art dual-compartment
front loading refuse vehicle of one type suitable for use
with the dual tailgate system of the invention;
Figure 2 is an elevational view of the rear of a
dual-compartment refuse container body utilizing the dual
tailgate system of the invention with the doors closed;
Figure 3 is a fragmentary side view of the end of
the container of Figure 2 showing both tailgates in the
closed, latched position;
Figure 4 is a view similar to Figure 3 with both
tailgates open; and
Figure 5 is a side view showing the tailgates in
both positions to depict the clearance achieved by the
system.
DETAILED DESCRIPTION
The multi-compartmented collection vehicle body
tailgate system designed of the present invention is
generally applicable to front and side loading rear
discharging collection vehicles and is characterized by
the ability to operate the tailgates independently while
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maximizing the retention of a low center of gravity
during the discharge operation. Refuse vehicles of the
class are generally characterized by a continuous,
permanent horizontal divider separating an upper
compartment from a lower compartment. The systems are
characterized by charging hoppers having separate
compartments each connected with an associated one of the
upper or lower storage compartments and separate fluid-
operated rams or compactor panels dedicated to compaction
or loading of materials into each of the compartments
materials and packing against a closed tailgate door
where appropriate.
In the drawings, Figure 1 depicts the side view of a
front loading refuse vehicle suitable for use with the
tailgate system of the invention. The vehicle is shown
generally at 10 with the sides removed to reveal some of
the interior details. The refuse hauling body includes a
refuse receiving area which is a chamber generally
divided into a forward section 14 which connects with a
lower loading hopper 16 which feeds a lower storage body
compartment 18. An upper loading hopper 20 has a
receiving opening rearward of the lower loading hopper 16
and is connected to an upper storage body compartment 22.
Lower storage body compartment 18 and upper storage body
compartment 22 are provided, respectively, with upper and
lower arcuate tailgates 24 and 26. These tailgates are
designed to absorb the forces of compaction and maintain
a pressurized load as necessary when closed. They swing
open to allow discharge of the refuse in the
corresponding storage body compartment. Each of the
loading hoppers is provided with a packing ram mechanism,
including a lower panel, generally at 28 and an upper
panel generally at 30. The body 12 is attached to a
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frame or chassis 32 which also carries a cab section 34
with door 35 and wheels at 36. A lift and dump
mechanism, shown generally at 38, is provided to empty
refuse containers into the receiving hoppers 14 and 18.
The lift and dump mechanism contains identical
devices addressing either side of the vehicle, one side
being depicted in Figure 1, including a heavy lift arm 40
which operates outside cab protector 42, lift and dump
hydraulic cylinders 44 and 46 and lifting fork 48. The
truck is shown about to address a refuse/recycle box 50
separated into a forward compartment 52 and a rear
compartment 54 by a vertical wall 56. One of two lift
handles designed to be addressed by the forks 48 is shown
at 58.
A representative embodiment of the tailgate system
of the invention which is suitable as a retro fit to a
multi-compartment rear discharging collection body or to
be incorporated in the construction of new bodies is
depicted in Figures 2-5. Figure 2 depicts a rear view of
a truck body or container, generally at 60, with both an
upper door 62 and a lower door 64 in a closed position.
An intermediate hinged auxiliary closure panel device
between the doors 62, 64 is shown at 66 and is used for
closing the upper portion of the lower compartment as is
better seen in Figures 3 and 4 which depict an
intermediate generally horizontal divider wall 68 which
separates the storage volume into upper and lower storage
compartments in the manner illustrated in Figure 1.
The upper door 62 is designed to completely close
the discharge opening of the upper compartment and is
hinged to lift and pivot vertically using a pair of
spaced opposed hinge systems 70, each of which includes
an arcuate shape extension member 71 hinged in a vertical
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slot 72 using associated follower hinge pin 74. The door
is operated by a pair of oppositely disposed fluid
cylinders as at 76 with rods as at 77 which are designed
to lift the door and swing it out as shown in Figures 4
and 5. The door is provided with a latch including a
pair of vertical latch members as at 78 which nest in
corresponding upward directed hook members as at 80 as
the closed door is lowered so that latching and
unlatching is automatically achieved by vertical
displacement of the door prior to opening or after the
door swings shut, utilizing the cylinders 76. Door 62 is
shown in the raised but yet unopened position in Figure 3
with the pin 74 at the top of slot 72, fully opened in
Figure 4 and in both the closed, latched and fully opened
positions in the clearance illustration of Figure 5. The
door is stiffened as by a frame of structural members one
of which is shown at 81.
The lower door 64 is spaced beneath the upper door
62 and is of similar construction in many respects. The
door 64 features a pair of vertically displaceable hinge
systems 82 which are of a construction somewhat similar
to that of the hinge system 70 utilized for the upper
door 62. The hinge systems 82, thus, include shaped
extension members 83, slots 84 and pin followers 86 which
enable the hinges (and the door 64) to be displaced
vertically prior to swinging open in the manner of the
door 62 in order to accomplish automatic latching and
unlatching. Hook members as at 89 nest in openings in
the structure when the closed door is lowered. The lower
doors 64 further include stiffener struts as at 87 and
lower structural extensions 88 to which is fixed a rear
bumper member, which may be a continuous structural
channel shown at 90.
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As can be seen in the figures, the operating
clearance required between the doors 62, 64 mandates a
minimum vertical gap between the doors. In this
embodiment, the lower door is of a reduced height
insufficient to accomplish full closure of the lower
compartment 18, a gap existing in the upper portion
thereof. The gap, of course, allows full opening of the
lower door 64 with the upper door 62 in the fully closed
and latched position as shown in Figure 5. Full closure
of the lower compartment is accomplished by the addition
of the further hinged panel member or auxiliary closure
device 66 which is suspended at the top of the lower
compartment in a manner which enables it to freely swing
vertically. As can be seen in the figures, and
particularly in Figure 2, the lower portion 92 of the
auxiliary closure device or panel 66 is captured behind
the upper portion of door 64 when it is in the closed
position, thereby effecting closure of the remainder or
upper portion of the lower compartment of the refuse
body. As shown best in Figure 4, the auxiliary closure
member 66 is free to swing open with the door 64 once
released by the raising of door 64. This allows full
opening of the lower compartment for discharge. The door
64 is further operated by a fluid cylinder 94 with rod 96
which raises and swings open the door in the same manner
as cylinder 76 operates door 62. As can be seen in the
diagram of Figure 5, doors can be in any position at any
time without interfering with each other. The convex
nature of the shape of the doors 62 and 64 better enables
them to operate as pressure vessel ends so that material
can be compacted against them and yet allows them to have
their maximum protrusion located off center so that they
do not interfere with each other.
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It can thus be seen from the above descriptions that
the tailgate system of the present invention allows and
full and independent operation of the plurality of
discharge doors to accommodate maximum flexibility in a
rear-discharge multi-compartment collecting container.
It will further be appreciated that by hinging the
lower door at a relatively low point, the center of
gravity as raised a minimal amount when both doors are
opened. It will further be recognized that the truck
body used may be one which raises and dumps trash to aid
material discharge although that model is not
illustrated. That, of course, would not alter the nature
of the tailgate system.
This invention has been described herein in
considerable detail in order to comply with the patent
statutes and to provide those skilled in the art with the
information needed to apply the novel principles and to
construct and use such specialized components as are
required. However, it is to be understood that the
invention can be carried out by specifically different
equipment and devices, and that various modifications,
both as to the equipment and operating procedures, can be
accomplished without departing from the scope of the
invention itself.
What is claimed is:
